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In this study, 15 patients (4 men and 11 women, mean age: 50 +/- 13 years) with unilateral adrenal masses detected on ultrasound (US), Computed Tomography (CT) and/or Magnetic Resonance (MR) studies were submitted to positron emission tomography (PET) with fluorine-18 deoxyglucose (FDG). Histology demonstrated 3 adenomas, 1 myelolipoma, 1 angiolipoma, 1 neurinoma, 1 cyst, 1 malignant pheochromocytoma, 4 carcinomas and 3 metastases. The patient population was divided into two groups. Group 1 (n = 7) consisted of benign adrenal lesions. Group 2 consisted of malignant adrenal tumors. Lesion measurements were performed on the basis of the results of US, CT and/or MR images. In Group 1, no FDG uptake was observed in adrenal masses. Conversely, in Group 2 adrenal lesions showed abnormally increased FDG uptake, suggesting high glucose tumor metabolism. No significant difference in lesion size was observed between Groups 1 and 2 (5.6 +/- 4.0 vs 6.3 +/- 3.0 cm). Furthermore, in 6 patients of Group 2, total body PET images showed abnormal FDG uptake in extra-adrenal locations, such as chest (n = 2) and abdominal (n = 5) lymph nodes, lungs (n = 6), liver (n = 5), pancreas (n = 1), bone (n = 1) and muscle (n = 1) tissues. In conclusion, the results of this study suggest that PET imaging with FDG can characterize adrenal masses. In particular, abnormally increased FDG uptake in adrenal malignancies allows to differentiate these abnormalities from benign lesions. Furthermore, total body imaging PET can identify extra-adrenal tumor sites in patients with malignant tumors.

Background The clinical impact of the positivity of the Deauville scale (DS) of positron emission tomography (PET) performed at the end of doxorubicin, bleomycin, vinblastine and dacarbazine (ABVD) in patients with advanced Hodgkin lymphoma (HL), in terms of providing rationale to shift poor responders onto a more intensive regimen, remain to be validated by histopathology. Patients and methods This prospective trial involved patients with stage IIB/IV HL who after six ABVD cycles underwent PET (PET6) and core-needle cutting biopsy (CNCB) of 2-deoxy-2[F-18] fluoro- d -glucose (FDG)-avid lymph nodes. Patients received high-dose chemotherapy/autologous haematopoietic stem cell rescue (HDCT/AHSCR) if CNCB was positive for HL, alternatively, if CNCB or PET was negative, received observation or consolidation radiotherapy (cRT) on residual nodal masses, as initially planned. The end-point was 5-year progression-free survival (PFS). Results In all, 43 of the 169 (25%) evaluable patients were PET6 positive (DS 4, 32; DS 5, 11). Among them, histology showed malignancy (HL) in 100% of DS 5 scores and in 12.5% of DS 4 scores. Fifteen patients with positive biopsy received HDCT/AHSCR, whereas 28 patients with negative biopsy, as well as 126 patients with negative PET6, continued the original plan (cRT, 78 patients; observation, 76 patients). The 5-year PFS in the negative PET6 group, negative biopsy group and positive biopsy group was 95.4%, 100% and 52.5%, respectively. Conclusion DS positivity of end-of-ABVD PET in advanced HL carried a certain number of CNCB-proven non-malignant FDG-uptakes. The DS 4 scores which were found to have negative histology appeared to benefit from continuing the original non-intensive therapeutic plane as indicated by the successful outcome in more than 95% of them by obtaining similar 5-year PFS to the PET6-negative group. By contrast, the DS 5 score had consistently positive histology and was associated with unsuccessful conventional therapy, promptly requiring treatment intensification or innovative therapeutic approaches.

Angiomyolipomas (AMLs) are among the most common benign renal tumors, typically consisting of varying proportions of 3 components: blood vessels (angio), smooth muscle cells (myo), and fatty tissue (lipoma), and are thus called triphasic. Occasionally, AMLs may present atypical histologic features consisting almost exclusively of one component (monophasic) or containing numerous epithelioid muscle cells with small amount of fat, as in the rare epithelioid variant (E-AMLs). AMLs occur as a sporadic entity in 80% of cases; more rarely, they are related to hereditary diseases such as tuberous sclerosis complex (TSC). Hereditary AMLs can reach huge dimensions and may present unusual imaging features determining diagnostic pitfalls. Few cases of giant sporadic AMLs are reported in literature, and even fewer regarding the epithelioid variant. We present a case of a 36-year-old man suffering from anemia and fever, whose contrast-enhanced computed tomography (CT) depicted the presence of a huge (14 x 21 x 30 cm) retroperitoneal fat-containing mass.

Objective The current methods of detection of recurrent colorectal cancer after surgical treatment are inaccurate using conventional imaging. This study set out to detect early recurrence by means of PET in patients treated surgically for colorectal cancer by curative resection. Methods Thirty-one disease-free patients were recruited and underwent FDG-PET. The results were verified by clinical, surgical and radiological follow up and/or biopsy to evaluate the accuracy for detecting recurrence. Results PET detected 6 sites of increased activity in 5 patients. Three of these underwent surgery. One was false positive with no evident tumour and two underwent an hepatic resection with removal of a homental metastasis. The sensitivity was 100% and specificity 83.3%. Clinical management was altered in two cases (6.4%). Conclusions This study demostrates that PET is more accurate than conventional imaging for the evaluation of recurrence in colorectal cancer patients. FDG-PET should be considered in the follow-up of patients after treatment for colorectal cancer in addition to other imaging methods.

Tc-99m MIBI imaging has been used to evaluate patients with different neoplastic disorders, but its role in nuclear oncology has not been definitely established. In this study, we compared the results of Tc-99m MIBI (planar and SPECT imaging) with those of F-18 FDG PET radionuclide studies in 19 patients who had proven lung cancer. One patient was studied in follow-up. All patients underwent chest CT scans. MIBI and FDG images were qualitatively and quantitatively analyzed using region of interest analysis. Quantitative evaluation of MIBI and FDG activities in lung-tumor lesions was performed calculating tumor/nontumor ratios. On CT, 18 lung tumors were detected, while one patient was disease free. For lung lesions, the diagnostic sensitivity of planar MIBI imaging was 83%, while those of MIBI SPECT and FDG PET were both 100%. The quantitative analysis of lung-tumor MIBI and FDG activities showed that FDG uptake was significantly (P < 0.001) higher compared with MIBI uptake (5.5 +/- 3.1 vs 2.1 +/- 0.6); concordant MIBI and FDG images were found in 4 lesions in terms of central activity defect showing central necrotic tumor tissue. For lymph node abnormalities, planar MIBI scan only detected 3 lesions in 3 patients, whereas MIBI SPECT identified 9 lesions in 5 patients. FDG PET showed 13 lymph node abnormalities in 5 patients. This study shows similar results of Tc-99m MIBI SPECT and F-18 FDG PET in the diagnostic evaluation of patients with lung tumors. However, FDG lung tumor uptake was significantly higher compared with MIBI accumulation, suggesting a high glucose tumor metabolism. Thus, MIBI SPECT imaging may be useful to evaluate such patients and may be considered an alternative when PET is not available

The aim of this study was to evaluate the role of radionuclide imaging in the characterization of nonhypersecreting adrenal masses.A total of 54 patients (19 men, 35 women; mean age, 50 +/- 16 y) with nonhypersecreting unilateral adrenal tumors that had been originally detected on CT or MRI underwent adrenal scintigraphy using different radiotracers. None of the patients showed specific symptoms of adrenal hypersecretion. Screening tests for excess cortical and medullary products showed normal adrenal hormone levels. Radionuclide studies (n = 73) included (131)I-norcholesterol (n = 24), (131)I-metaiodobenzylguanidine (MIBG) (n = 23), and (18)F-FDG PET (n = 26) scans.Histology after surgery (n = 31) or adrenal biopsy (n = 23) was obtained. Adrenal lesions were represented by 19 adenomas, 4 cysts, 1 myelolipoma, 1 neurinoma, 2 ganglioneuromas, 5 pheochromocytomas, 4 pseudotumors, 6 carcinomas, 2 sarcomas, and 10 metastases (size range, 1.5- to 5-cm diameter; mean, 4.9 +/- 3.1 cm). For norcholesterol imaging, diagnostic sensitivity, specificity, and accuracy were 100%, 71%, and 92%, respectively; the positive predictive value (PPV) of the norcholesterol scan to characterize an adrenal mass as an adenoma was 89%, whereas the corresponding negative predictive value (NPV) to rule out this type of tumor was 100%. For MIBG imaging, diagnostic sensitivity, specificity, and accuracy were 100%, 94%, and 96%, respectively; the PPV of the MIBG scan to characterize an adrenal mass as a medullary chromaffin tissue tumor was 83%, whereas the corresponding NPV to rule out this type of tumor was 100%. For FDG PET, diagnostic sensitivity, specificity, and accuracy were 100%, 100%, and 100%, respectively; the PPV of FDG PET to characterize an adrenal mass as a malignant tumor was 100%, whereas the corresponding NPV to rule it out was 100%. Furthermore, in 7 patients with malignant adrenal tumors, FDG whole-body scanning revealed extra-adrenal tumor sites (n = 29), allowing an accurate diagnosis of the disease's stage using a single-imaging technique.In patients with nonhypersecreting adrenal masses, radionuclide adrenal imaging, using specific radiopharmaceuticals such as norcholesterol, MIBG, and FDG, may provide significant functional information for tissue characterization. Norcholesterol and MIBG scans are able to detect benign tumors such as adenoma and pheochromocytoma, respectively. Conversely, FDG PET allows for recognition of malignant adrenal lesions. Therefore, adrenal scintigraphy is recommended for tumor diagnosis and, hence, for appropriate treatment planning, particularly when CT or MRI findings are inconclusive for lesion characterization.

OBJECTIVE: The aim of this study was to differentiate benign from malignant adrenal tumors using positron emission tomography (PET) with 18F-fluorodeoxyglucose (FDG) in patients with unilateral adrenal masses originally detected by CT or MR imaging. CONCLUSION: PET imaging with FDG can metabolically characterize adrenal masses. Abnormally increased FDG uptake in adrenal malignancies allows one to differentiate these abnormalities from benign lesions. Whole-body PET can also reveal extraadrenal tumor sites in patients with malignant tumors, using a single imaging technique for accurate disease staging.